Stainless emulsible grease



Patented June 3, 1952 STAINLESS EMULSIBLE GREASE Jere C. Showalter, Baytown, Tex., assignor, by

mesne assignments,

Standard Oil Development Company, Elizabeth, N. J., a corporation of Delaware No Drawing. Applicationjune 21, 1950, Serial No. 169,512

3 Claims.

The present invention is directed to a stainless, emulsible grease composition which may be employed in pipe bending and wire drawing operations and the like.

The stainless, emulsible grease composition of the present invention comprises a composition having as major ingredients an alkaline base oil containing alkali metal petroleum sulfonates and a hydrocarbon in the lubricating oil boiling range having a viscosity at 100 F. of 75 to 500 SSU and a solid having lubricating properties selected from the class consisting of talc and mica and minor amounts of tall oil, a polyhydroxy alcohol, an oil soluble corrosion inhibitor and a fatty acid. The solid having lubricating properties is employed in a ratio of at least 1:2 to said alkaline base oil.

The composition of the present invention contains an alkaline base oil which includes an alkali metal petroleum sulionate and a hydrocarbon in the lubricating oil boiling range having a viscosity of 75 to 500 SSU at 100 F. The alkaline base oil may be prepared preferably by exhaustively sulfonating with concentrated sulfuric acid a solvent extract of a lubricating oil fraction obtained from a naphthenic base crude, such as a lubricating oil fraction from a coastal crude. For example, a phenol extract of a lubricating oil fraction from a coastal crude having a viscosity of approximately 75 SSU at 100 F. may be exhaustively treated with concentrated sulfuric acid, the sludge separated and the acid oil neutralized with caustic alkali, such as sodium hydroxide and the neutralized oil, which may contain an excess of caustic alkali, finished by blowing with air to remove moisture. The finished base oil contains from to by weight of alkali metal petroleum sulfonates in addition to some excess caustic alkali with the remainder being unsulfonated oil.

The hydrocarbon oil and sulfonates which may contain a sufiicient amount of caustic alkali to make the mixture alkaline may be prepared by admixing petroleum sulfonates, a hydrocarbon in the lubricating oil boiling range having the viscosity mentioned before and a small amount of a caustic alkali. The hydrocarbon oil ordinarily boils in the lubricating oil boiling range and should have a viscosity of '75 to 500 SSU at 100 F. and should be relatively free of arcmatic hydrocarbons. The alkaline base oil produced, as mentioned before by exhaustively sulfonating a phenol extract of a naphthenic lubricating oil fraction, may contain alkali metal petroleum sulfonates having in the range from about 325 to 400. The alkaline base oil may be employed in the composition of the present invention in an amount in the range from to 75% by weight with a preferred concentration in the range between 50% to 60% by weight. The petroleum sulfonates consist of molecular weights Table I Weight Per Cent Alkaline Base Oil Petroleum Sulfonat Oil' Tall Oil-M-.-

Polyliydroxy Cyclohexylamine Fatty Acid Tale or Mica Ratio to Base Oil llllllll swm a F nesse-mm The tall oil which is employed in my improved grease serves to impart adhesive powers to the mixture and may be employed in the grease composition in an amount in the range from about 0.5% to about 2% by weight, although it is preferably employed in an amount in the range from 0.5% to 0.6% by weight.

The polyhydroxy alcohol which imparts water emulsibility to the composition may be employed in an amount in the range from 0.5% to 2.0% by weight and preferably is employed in an amount in the range between 0.5% to 0.6% by weight. As examples of the polyhydroxy alcohol may be mentioned glycerine, propylene glycol, diethylene glycol, triethylene glycol, and the like. Other polyhydroxy alcohols may be used provided they are water soluble and miscible with the composition.

The corrosion inhibitor is preferably cyclohexylamine and should be present in a concentration of at least 0.3% by weight. The amount of corrosion inhibitor will depend on the particular corrosion inhibitor employed but ordinarily will not exceed 1% by weight of the composition but preferably will be in an amount in the range of 0.4% and 0.5% by weight of the composition. As a general statement, it may be 7 said that the corrosion inhibitor may be 011 soluble. Examples of the oil soluble corrosion inhibitors are: phe'nylalphanaphthylamine, dicyclohexylamine, isooctylphenolmethylamine, and the like.

The fatty acid is employed in the composition of the present invention to improve the lubricating properties of the mixture. The fatty acid may also react with some of the excess alkali in the alkaline base oil and form, for example when stearic acid is employed, the stearate which improves the lubricating properties of the mixture and imparts increased bearing strength and acts as a soap. or emulsifying agent to allow the improved grease to be removed by washing the surface, to which it is applied, with water. Ordinarily the concentration of the fatty acid will be in the range from 0.05% to 0.2% by weight of the composition. Preferably it will be used in a concentration in the range from 0.09% to 0.1% by weight. Stearic acid is the preferred fatty acid but other fatty acids and fatty acid-containing materials may be used in lieu of, stearic acid. For example, lard oil, oleic acid, palmitic acid, la-uric acid, Wool, fatty acids, tallow oil, linoleic acid and the like may be used.

The other major component of the composition of the present invention is a solid having lubricating properties selected from the class consisting of talc and mica. The amount of the 7 solid having lubricating properties is dependent on the desired viscosity of the improved grease but generally the solid may be present in a concentration of about 33%. Stating this otherwise, the ratio of the solid such as talc or mica to the alkaline base oil should be at least 1:2 and generally should not exceed about 70% by weight of the composition or a ratio of 2:1 with respect to the alkaline base oil. If too much of the solid, such as talc or mica is used, the grease is very viscous so that the upper limit of the solids concentration depends on the viscosity, of the grease desired. A grease composition which has been used commercially in bending pipe having large diameters is given in the following table:

The grease having the foregoing composition is successfully used in bending pipe ina large petroleum refinery. Equipment used for bending pipe of large diameter operates by holding the pipe to be bent adjacent to a large circular wheel while applying a block to the surface of the pipe opposite the pipe surface in contact with the wheel. The pipe and the wheel are slowly rotated with respect to one another. A close fitting, highly polished metal plug is placed in the pipe and travels inside the pipe just ahead of that portion of the pipe that is being bent, thus preventing the formation of wrinkles in the inner portion of the bend. The plug travels through the pipe ahead of the bend by virtue of the pres sure exerted upon it by the attempt of that portion of the pipe which is being bent to collapse. In order for this plug to travel smoothly inside the pipe, it is necessary that the inner surface of the pipe be well lubricated. Ordinary oil will not sufiice for this purpose because the heat caused by the bending operation makes the oil so fluid that it runs entirely to the lower surface of the pipe, thus leaving large areas of the pipe insufiiciently lubricated. The usual preparation used for this lubrication is a grease which is moderately viscous at room temperature and which contains large quantities of graphite. This grease is sprayed on the inner surface of the pipe by means of a suitable moving spraying device and the plug is then inserted through the open end of the pipe and slid over this lubricated surface to the point at which the bend is to be started. When the bending operation is complete, the plug and excess grease are removed. This grease, by virtue of the large quantity of graphite contained therein, is very messy to handle and diflicult to clean from the equipment and the operator and, therefore, unsatisfactory. In addition, when it is wiped from the plugs before they are stored, it leaves the highly polished surface of the plugs exposed to the air which causes them to corrode unless they are protected by means of a compound which must be coated over them until they are again to be used.

The composition of the present invention which includes a solid which does not soil surfaces with which it comes in contact serves to give the needed viscosity to the lubricating composition and furthermore it contains ingredients which allow it to be readily removed by washing with water thus making it easy to clean the metal plugs employed in such pipe bending operations. The presence of the corrosion inhibitor prevents rusting of the surfaces which have been treated with the grease and protects them from corroding during storage periods.

The composition of the present invention has been accepted commercially in pipe bending operations due to its stainless qualities and ease of removal by virtue of its eliminating the necessity of employing graphite and by virtue of its being readily soluble with water.

The nature and objects of the present invention having been fully described and illustrated, what I desire to claim as new and useful and to secure by Letters Patent is:

1. A stainless, emulsible grease composition which comprises 25% to 75% by weight of a base oil containing alkali metal petroleum sulfonates in an amount in the range between 10% and 15% by weight of said base oil, the remainder being a hydrocarbon in the lubricating oil boiling range, 0.5% to 2.0% by weight tall oil, 0.5% to 2.0% by Weight of a polyhydroxy alcohol, 0.3% to 1% by weight of an oil soluble corrosion inhibitor, 0.05 to 0.2% by weight of a fatty acid, and a solid having lubricating properties selected from the class consisting of talc and mica in a ratio in the range between 1:2 and 2:1 to said base oil.

2. A stainless, emulsible grease composition which consists of about 60% by weight of a base oil containing alkali metal petroleum sulfonates in an amount in the range between 10% and 15% by weight of said 011 and the remainder a hydrocarbon oil having a viscosity at F. of 75 to 500 SSU, about 0.6% by weight tall oil, about 0.6% by weight diethylene glycol, about 0.4% by weight cyclohexylamine, about 0.1% by weight stearic acid and about 38% by weight of a solid having lubricating properties selected from the class consisting of mica and talc.

3. A composition in accordance with claim 2 in which the hydrocarbon oil is substantially free of aromatic hydrocarbons.

JERE C. SHOWALTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,617,455 Montgomery Feb. 15, 1927 1,781,607 Stamberg Nov. 11, 1930 1,317,599 Adams et al Aug. 4, 1931 2,112,632 Montgomery Mar. 29, 1938 2,444,271 Smith June 29, 1948 2,490,949 De lorenzo Dec. 31, 1949 FOREIGN PATENTS Number Country Date 660,799 France Feb. 25, 1929 

1. A STAINLESS, EMULSIBLE GREASE COMPOSITION WHICH COMPRISES 25% TO 75% BY WEIGHT OF A BASE OIL CONTAINING ALKALI METAL PETROLEUM SULFONATES IN AN AMOUNT IN THE RANGE BETWEEN 10% AND 15% BY WEIGHT OF SAID BASE OIL, THE REMAINDER BEING A HYDROCARBON IN THE LUBRICATING OIL BOILING RANGE, 0.5% TO 2.0% BY WEIGHT TALL OIL, 0.5% TO 2.0% BY WEIGHT OF A POLYHYDROXY ALCOHOL, 0.3% TO 1% BY WEIGHT OF AN OIL SOLUBLE CORROSION INHIBITOR, 0.05% TO 0.2% BY WEIGHT OF A FATTY ACID, AND A SOLID HAVING LUBRICATING PROPERTIES SELECTED FROM THE CLASS CONSISTING OF TALC AND MICA IN A RATIO IN THE RANGE BETWEEN 1:2 AND 2:1 TO SAID BASE OIL. 